It’s hard to argue with the findings and conclusions of a new paper in JAMA put forth by Drs. Lydia Pace and Nancy Keating, both physicians with public health degrees and appointments at Harvard-affiliated hospitals. The article, published on April 2, has generated a predictable round of headlines along the lines of “Large Study Finds Little Benefit in Mammography.”

You might, while reading or hearing about this news, wonder about the value of yet another study on breast cancer screening. And you might, if you are following this blog, wonder why I remain convinced that mammography – when done right – has the potential to save many women’s lives and, what’s more, to spare even more from the physical, financial and emotional toll of prolonged treatment for advanced-stage disease.

Why I still think that breast cancer screening is a good idea for most middle-aged women (selected, from a longer list):

1. Several valid studies, most notably that from Sweden, have shown a significant survival benefit of breast cancer screening over the long term. These findings, which demonstrated a benefit to women screened in their forties, received little attention in the news.

2. Mammography is not all the same. It’s not a simple, black-and-white or numeric readout. The “result” depends a lot on the radiologist who interprets the images. Some radiologists, by their training and expertise, deliver lower false positive rates and higher true positive (malignant) “pickup” rates. To say that mammography doesn’t work, based on studies over a population, discounts the potential (and likely) benefit of having the procedure done by experts.

3. Pathology methods have improved over the past three decades. Some doctors, including epidemiologists and PCPs, may not be aware of new tools for evaluating tumors that lessen the risk of over-treating early-stage and indolent tumors.

4. Longer survival is not the only benefit of mammography. Late detection involves risks, and costs. “Screening neglect,” as some researchers call it, adds intensity to needed treatment when patients first seek care for advanced disease. This was the focus of a recent paper in the American Journal of Roentgenology that got little press except for the Cleveland Plains Dealer. The investigators in that careful but retrospective analysis found that among women in their forties, breast cancers detected in routine mammograms were significantly smaller than those detected in women who waited until they felt a lump or had symptoms. That finding was no surprise. But what mattered is that the difference in size of invasive breast cancers found – between screened and unscreened women – translated to less chemotherapy for those screened. The point: finding breast cancer early can reduce the need for toxic and costly treatment.

In reading the new JAMA paper, “A Systematic Assessment…” it seems like the authors are giving a well-prepared talk. Essentially it’s a review of reviews on mammography. Yes, it’s that “meta.” They examined the literature on mammography, going back to 1960 – but with an appropriate emphasis on more recent studies, to address 4 (huge, complex) questions: 1) what is the benefit of mammography screening, and how does it vary by patient age and risk?; 2) what are the harms of mammography screening?; 3) what is known about personalizing screening recommendations? 4) how can patients be supported to make more informed decisions about screening?

This is an ambitious set of questions, to say the least. The tables provided, which are for the most part inconclusive, draw heavily on findings that vary in the era of data collected, methods of analysis, and reasonableness of authors’ assumptions, i.e. validity.

But there is no news on mammography here, except that these two thoughtful investigators carefully reviewed the literature. There are no original data in this ambitious analysis, i.e. there is no new information about mammography’s effectiveness, the false positive rate, the harms of screening, overdiagnosis, etc.

Unfortunately the article, at a glance, may add to the growing perception among journalists, primary care physicians who may not read below the paper’s title, and others – including many ordinary women – that mammography’s effectiveness has been, again, disproved. And so if journalists cover this “story,” as they have and will, our collective memory will incorrectly recall another negative finding, which this is not.

The authors’ main conclusions are that decision aides may be helpful, and that developing better ways of screening for breast cancer would be even better than that. I agree.

Lately I’ve been thinking a lot about the value of patients’ voices. As a doctor, I was trained to be somewhat skeptical of what people say, or admit, about their conditions. I was told, though never inclined, to steer the conversation, the history-taking part of the exam, to get the patient’s story in a way that fit succinctly, to answer the questions I was required to ask. The goal of the interview was to form a reasoned opinion about what might be ailing the person, i.e. a diagnosis – and, later, to establish a plan to help make the person feel better.

Journalists, whether they’ll say so or not, tend to do the same. They write an article with a purpose, on assignment or otherwise. And they’ll interview people with the goal of getting pithy quotes to make a point. And they’ll take the words other people and chop ‘em up, and present those to relate a certain narrative. Here too, I’m guilty.

But my point here, today, is about truth, and where the most credible information can be found. Can you trust a selfie?

When I glanced through yesterday’s paper on-line, I read a wrenching account of child abuse. The story, presented in the form of a letter, came through Nick Kristof, a reliable source in my view. I value his columns on environmental and women’s health. When I read the letter he presented, by Dylan Farrow, detailing the humiliating experiences she had as a young child in the home of her adopted mother, Mia Farrow, and the filmmaker Woody Allen, I was stopped by revulsion. Her depiction of an incident had the immediate effect of making me never wish to see another of Allen’s films again. Later on, I read Kristof’s regular NYT column, which includes just a clipped segment of the letter. The picture clouded. He makes a point with which I agree, fully – that girls and women who claim to have been assaulted, or abused, should be taken seriously. But I found myself wondering: how do we know what Dylan says is true?

I’m struck by how two versions of the same story, offered by one journalist, led me along diverging sympathies. One, in which the young woman’s testimony is included fully, left me feeling convinced that the filmmaker, who’s created many of my favorites, shouldn’t receive awards and, in fact, deserves punishment. The other, in which the journalist presents parts of her letter in the context of his admitting a relationship with the family and some legal issues around the case, left me wondering if the celebrity is a victim of finger-pointing or distorted recollections of things that happened to a child a long time ago.

The bottom line is that I certainly can’t know what happened, nor can most readers. Memory of pain, illness, trauma and ordinary experience is subjective.

Getting back to medicine –

Few journalists I know would want a doctor to not listen attentively to their account of their illness, however long. Many doctors claim they’re giving patient-centered care, but are they really listening to their patients’ stories? How do professionals count, or discount, an individual’s rendition of a story, and render a diagnosis or prescription?

My only conclusion is that it’s usually worth hearing what a person says, directly. She is a key witness to her experience. Doctors and journalists may aspire to being more objective, by documenting what happened to a person or group. They draw their own pictures, or graphs, and offer separate explanations of events and phenomena. But they make edits all the time, consciously and otherwise.

For this week, I refer my readers to the generous, telling blog of Lisa Bonchek Adams, a woman who is 44 years old and lives with Stage 4 breast cancer. She has spent the past week holding firm at the center of a media-storm, while hospitalized.

I know Lisa and admire her for her candor. It takes courage to share what it’s like, as she does – good days and bad. Yes, her story is imperfect. But so is everyone’s.

I see beauty in her story, unedited.

Lisa’s blog and tweets are not filtered by a journalist, nor structured by a doctor to fit into an HPI or EHR. She writes directly to her readers. If you insist on literature, you might consider Lisa’s work as a splintered and intensely personal longform narrative.

The blog is kind of like a thick, old-style paper chart of a complex patient. A doctor, in trying to understand a person’s course, might read all of it, or flip through most, or just cut to the chase and scan a few recent lines and lab values. It takes time to pour through a detailed account, to appreciate what is really going on, to understand what the notes reflect.

It could be that there is no “answer,” that Lisa’s story is, plainly, what it is – about her life. Not everything needs be explained. Why peg a person’s condition? Except maybe if you’re a doctor and she’s asking you for treatment or advice.

Lisa is not asking for a diagnosis. She has a team of doctors. She is just letting you know what it’s like to be in her circumstances, in case you’re interested, or care.

I learn a lot from Lisa. I am glad that she is alive and tweeting, as she chooses.

Yesterday I learned that a woman I know slightly, a journalist, has Stage 4 lung cancer. Debra Sherman is a reporter for Reuters and began a blog, Cancer in Context. It’s a moving start of what I hope is a long journey.

What struck me is how Debra describes crossing a line, a bit the way I felt when I found out I had breast cancer. She writes:

I have been writing about medical technology and healthcare for more than a decade. I’ve covered the major medical meetings, including the big one on cancer. I’ve written stories about new cancer drugs and treatments…I wrote those stories objectively and never imagined any would ever apply to me.

She’s shifted from what you might call a “straight” reporter to an i-reporter journalist. And although it’s true that Debra may be less objective than some other writers on the subject, she’s already knowledgeable – through her prior work – on many of the relevant terms and issues. Much of what she knows already, vocabulary included, may allow her to make more informed decisions. It’s possible it may enable her to write in a way that helps readers more than ever.

Earth, from space (NASA image, Wiki-commons

I wish her the best with her column, and with her health ahead.

The bigger issue, of which the story reminds me, is that we’re living among too many young and middle-aged people who have cancer. Every day I read or hear of another case among my neighbors, a friend, a blog. Each reminds me of the need for research, better drugs, and greater knowledge of why so many tumor types – including lung cancer in women who haven’t smoked much, and breast cancer in young women – are on the rise.

The ASCO meeting, where believe me I wish I could be but can’t now, offers a bright picture for targeted drugs, genomics, novel immunotherapy and better data access and analyses through a huge new platform called CancerLinQ, All good. Great, really.

In thinking about each new case in my “world” – if I could pick a field for future investigation that might lead to insight on cancer’s causes and, ultimately, reduce the cancer burden 30 and 50 years from now, I might choose the tiny, under-funded area of environmental oncology

That’s a tough field. Most oncologists want to work with patients. Researchers want to publish papers. Cause-and-effect is hard to demonstrate, especially when most of the data is untenable and you’re up against businesses, politics and people who, understandably, don’t recall precisely what they ingested years ago. But to stop cancer from happening so much, that’s where the money is. IMO, nothing more.

Before I became a journalist, I rarely talked about my medical problems. When I was working at the hospital I tried not to mention, or show, the pain I was experiencing in my back to colleagues or even friends. Eventually I had to tell a higher-up about it, because I didn’t take narcotics and the pain became limiting. Rounding was difficult. I needed a chair.

And so I was struck by an essay in today’s Times by a woman who has dystonia, a neurological condition. She writes:

Long after “coming out” to my friends about my diagnosis, I realize now that what’s most important is telling people about the disease. Telling waiters why I’ve brought a special pillow with me to a restaurant; legislative aides who want to know what their bosses can do; and strangers who ask, almost rhetorically, if I am in pain.

The point of the article, as I understand it, is that big-name diseases like cancer get loads of media attention and sympathy from strangers. Relatively few people “get” the suffering of those with rare or less mortifying conditions. This is especially true when there’s no celebrity who speaks, writes, sings or otherwise whines or rails on it. People who don’t feel well want empathy, or at least a bit of consideration.

OK, now I’m going to say what’s hard, and I might regret, but I’m not sure that everyone needs to hear about all of our ailments: Sure, if you’re a writer, you can sort through your medical issues and feel better by expressing yourself, as I sometimes do here, and in principle and occasional reality help others facing similar disorders. And if you’re an employee somewhere and you need to take time off or accommodation for a disability, you may need to talk with your boss about what’s going on.

But do you need explain to the person on the checkout line or, say, a mother organizing a bake sale, why your back hurts? Why you frequent the women’s room? Or why you need a seat on the bus?

I am truly ambivalent about this.

My only way out is to tell you of an error I think I made, in withholding information. After my spine surgery, when I couldn’t sit up without assistance, or raise my arm to brush my teeth, and then eventually was practicing walking with a cane, wearing a brace in warm weather under modest clothing, I deliberately didn’t visit or walk by my place of work. I didn’t want my colleagues to see me looking frail. I wanted to return to work looking strong and standing straight up, as if nothing were wrong inside.

Already I’d had the cancer treatment – surgery and chemo – and they knew about that, although we didn’t speak of it much. Mainly it was women coworkers who visited me when I was hospitalized. That is understandable. Most of my colleagues didn’t know about my back. Not really. A lot of people have back pain, after all. What’s the difference, scoliosis, fusion, a revision, a clot, whatever…Or about my other conditions. It was TMI.

Over time I was becoming a burden to the group and – astonishingly in retrospect, I felt badly about that. I worked harder than most, to compensate for my disability (which I had trouble acknowledging, internally), and that further damaged my health. I sometimes wonder, now, if I had told my colleagues earlier, and let my non-cancerous conditions “show,” would I still be practicing medicine today?

Maybe.

Not everyone wants to hear about it. Or know. Besides, plenty of people have stuff they don’t mention –

“Everything is copy,” is a phrase Nora Ephron learned from her mother. That’s according to her son, Jacob Bernstein, who detailed some of her final days in the New York Times Magazine. But Ephron kept quite a bit to herself. She was a sharp and successful lady.

Before this morning, I never wondered what it’s like to walk in Angelina Jolie’s shoes. Like many, I woke up to the news – presented in the form of an op-ed in the NYTimes – that one of the world’s most beautiful and famous women recently had bilateral mastectomies to reduce her risk of developing breast cancer.

It turns out the 37 year old actress carries a BRCA1 mutation, a genetic variant that dramatically ups her risk of developing breast and ovarian cancers. Her mother, Marcheline Bertrand, died of cancer at the age of 56 years. Jolie would have been 31 years old when her mother died.

As Jolie tells it, doctors estimated her risk of developing breast cancer to be 87 percent. As she points out, the risk is different in each woman’s case. As an oncologist-journalist-patient reading her narrative, I can’t help but know that each doctor might offer a different approximation of her chances. It’s likely, from all that Jolie has generously shared of her experience and circumstances, that her odds were high.

“Cancer is still a word that strikes fear into people’s hearts, producing a deep sense of powerlessness,” Jolie wrote in today’s paper. To take control of her fate, or at least to mitigate her risk as best she could upon consultation with her doctors, she had genetic testing for BRCA and, more recently, decided to undergo mastectomy.

The decision was hers to make, and it’s a tough one. I don’t know what I’d have done if I were 37 years old, if my mother died of cancer and I had a BRCA mutation. There’s no “correct” answer in my book, although some might be sounder than others –

I know physicians who’ve chosen, as did the celebrity, to have mastectomies upon finding out they carry BRCA mutations. And I’ve known “ordinary” women – moms, homemakers, librarians (that’s figurative, I’m just pulling a stereotype) who’ve elected to keep their breasts and take their chances with close monitoring. I’ve known some women who have, perhaps rashly, chosen to ignore their risk and do nothing at all. At that opposite extreme, a woman might be so afraid, terrified, of finding cancer that she won’t even go to a doctor for a check-up, no less be tested, examined or screened.

What’s great about this piece, and what’s wrong about it, is that it comes from an individual woman. Whether she’s made the right or wrong decision, neither I nor anyone can say for sure. Jolie’s essay reflects the dilemma of any person making a medical choice based on their circumstances, values, test results and what information they’ve been given or otherwise found and interpreted.

How to conclude? Mainly and first, that I wish Ms. Jolie the best and a speedy recovery after surgery. And to thank you, Angelina, for raising this issue in such a candid fashion.

As for the future, Jolie’s decision demonstrates that we need better (and not just more) research, to understand what causes cancer in people who have BRCA mutations and otherwise. My hope is that future women – children now –needn’t resort to, nor even contemplate, such drastic procedures to avoid a potentially lethal condition as is breast cancer today.

Recently I wrote a review of Between the Lines, a helpful handbook on bio-medical statistics authored by an acquaintance and colleague, Dr. Marya Zilberberg. In that post, I mentioned my concern about some of the assumptions and statements on mammography. One thing I liked the book, abstractly, is the author’s efforts to streamline the discussion so that the reader can follow the concepts. But simplification and rounding numbers, “for ease of presentation” (p. 29) can mess up facts, significantly in ways that some primary care doctors and journalists might not appreciate. And so I offer what I hope is a clarification, or at least an extension of my colleague’s work, for purposes of helping women understand the potential benefits and risks of mammography.

In the section on mammography (pp. 28-31), the author rounds down the incidence of breast cancer in women between the ages of 40 and 50 years, from “1 in 70” (1.43%) to “1 in 100” (1%). As any marketing professional might remind us, this small change represents a 30% drop (0.43/1.43) in the rate of breast cancer in women of that age group. This difference – of 30%, or 43%, depending on how you look at it – will factor into any calculation of the false positive (FP) rate and the positive predictive value (PPV) of the test.

For women ages 40-49

Have breast cancer

Don’t have breast cancer

If estimate 1 in 100, 1.0 %

100

9,900

If estimate 1 in 70, 1.43 %

143

9,857

Keep in mind that these same, proportional difference would apply to any BC screening considerations – in terms of the number of women affected, the potential benefits and costs, for the 22,996,493 women between the ages of 40 and 49 counted in the 2010 U.S. Census,

My colleague estimates, fairly for this younger age group of women (who are relatively disposed to fast-growing tumors), that the screening technology (mammography) only picks up 80% of cases; 20% go undetected. In other words – the test is 80% sensitive; the false negative, FN, rate is 20%. In this same section, she considers that the FP rate as 10%. Let’s accept this (unacceptably high) FP rate for now, for the sake of discussion.

As considered in Between the Lines:

If FP rate is 10%, prevalence 1 in 100

Really have BC

Don’t have BC

Total

Mammography +

80

990

1,070

Mammography –

20

8,910

8,930

Total

100

9,900

10,000

But the above numbers aren’t valid, because the disease affects over 1 in 70 women in this age bracket. Here’s the same table with a prevalence of 1 in 70 women with BC:

If FP rate is 10%, prevalence 1 in 70

Really have BC

Don’t have BC

Total

Mammography +

114

986

1,100

Mammography –

29

8,871

8,900

Total

143

9,857

10,000

In this closer approximation to reality, the number of true positives is 114, and false positives 986, among 1,100 abnormal screening results. Now, the PPV of an abnormal mammogram is 114/ (114+986) = 10.4%. So the main statistical point – apart from the particulars of this discussion – is that a seemingly slight rounding down can have a big impact on a test’s calculated and perceived value. By adjusting the BC rate to its prevalence of approximately 1 in 70 women between 40 and 49 years, we’ve raised the PPV from 7.5% to 10.4%.

Here I must admit that I, too, have rounded, although I did so conservatively very slightly. I adopted a 1 in 70 approximation (1.43%) instead of 1 in 69 (1.45%), as indicated on the NCI website. If we repeat the table and figures using a 1 in 69 or 1.45% prevalence rate and 6% FPS, the PPV rises a tad, to 10.5%.

Now, we might insert a different perspective: What if the false positive rate were 6%, as has been observed among sub-specialist radiologists who work mainly in breast cancer screening?

If FP rate is 6%, prevalence 1 in 70

Really have BC

Don’t have BC

Total

Mammography +

114

591

705

Mammography –

29

9266

9,295

Total

143

9,857

10,000

As you can see, if we use a FP rate of 6% in our calculations, the total number of FPs drops to 591 among 10,000 women screened. In this better-case scenario, the PPV of the test would = 114/ (114+591) =16%. Still, that’s not great – and I’d argue that public health officials, insurers and patients should be pushing for FP rates closer to 2 or 3% – but that’s irrelevant to my colleague’s point and her generally instructive work.

My second concern has to do with language, and making the consequences of false positives seem worse than they really are. On page 29, the author writes: “ So, going back to the 10,000 women being screened, of 9,900 who do NOT have cancer… 10%, or 990 individuals will still be diagnosed as having cancer.” The fact is, the overwhelming majority of women with positive mammograms won’t receive a cancer diagnosis. Rather, they’ll be told they have “an abnormal result, or a finding that suggests the possibility of cancer and needs further evaluation,” or something along those lines. It would be unusual in practice to jump from a positive mammogram straight to a breast cancer diagnosis. There are steps between, and every patient and journalist should be aware of those.

—
Finally, if I were to write what I really think, apart from and beyond Between the Lines – I’d suggest the FP rate should be no higher than 2 or 3% in 2012. This is entirely feasible using extant technology, if we were to change just two aspects of mammography practice in the U.S. First, require that all mammograms be performed by breast radiologists who get extra training and focus in their daily work almost exclusively on breast imaging. Second, make sonograms – which, together with mammograms, enhance the specificity of BC screening in women with dense breasts– universally available to supplement the radiologists’ evaluations of abnormal mammograms and dense breasts in younger women.

By implementing these two changes, essentially supporting the practice of sub-specialists in breast radiology, we could significantly lower the FP rate in breast cancer screening. The “costs” of those remaining FPs could be minimized by judicious use of sonograms, needle biopsies and other measures to reduce unnecessary surgery and over-treatment. Over the long haul, we need to educate doctors not to over-treat early stage disease, but that goes far beyond this post and any one woman’s analysis of mammography’s effectiveness.

What I see in this is first, a win for patients, who now are more likely to get health care if and when they need it – preventive and otherwise. L’Chaim!

Second, it’s a win for the Obama administration and the Democrats. And although I went to journalism school at Columbia University and was told that “real journalists don’t share their opinions,” I do: I’m a registered, reliable, primary-voting Democrat. The ACA is, so far, President Obama’s signature achievement. This SCOTUS decision supports the President’s goal of simultaneously reining in health care costs and expanding coverage to all. It raises the likelihood of President Obama’s re-election. Cheers!

Finally, and at a deeper level, the decision reflects the power of one man’s thoughtfulness to change the outcome of a seemingly bleak situation. (This can happen in oncology and other kinds of medicine, when most of the doctors or specialists on a case throw up their hands or say “it’s impossible because of blah, blah, blah,” and they might refer to some old published studies on old drugs, or something like that.) What Chief Justice Roberts did was think out-of-the box, carefully and within a legal framework. Like a good, smart doctor, morally grounded and, perhaps, influenced by compassion (hard to tell), the Chief Justice figured out a legally acceptable way for his court to do the right thing. By his wisdom, he will have saved more than a few lives. Bravo!

CER is a big deal in medicine now. Dry as it is, it’s an investigative method that any doctor or health care maven, politician contemplating reform or, maybe, a patient would want to know. The gist of CER is that it exploits large data sets – like SEER data or Medicare billing records – to examine outcomes in huge numbers of people who’ve had one or another intervention. An advantage of CER is that results are more likely generalizable, i.e. applicable in the “real world.” A long-standing criticism of randomized trials – held by most doctors, and the FDA, as the gold standard for establishing efficacy of a drug or procedure – is that patients in research studies tend to get better, or at least more meticulous, clinical care.

The JAMA program began with an intro by Dr. Phil Fontanarosa, a senior editor and author of an editorial on CER, followed by 4 presentations. The subjects were, on paper, shockingly dull: on carboplatin and paclitaxel w/ and w/out bevacizumab (Avastin) in older patients with lung cancer; on survival in adults who receive helicopter vs. ground-based EMS service after major trauma; a comparison of side effects and mortality after prostate cancer treatment by 1 of 3 forms of radiation (conformal, IMRT, or proton therapy); and – to cap it off – a presentation on PCORI‘s priorities and research agenda.

I learned from each speaker. They brought life to the topics! Seriously, and the scene made me realize the value of meeting and hearing from the researchers, directly, in person. But, NTW, on ML today we’ll skip over the oncologist’s detailed report to the second story:

Dr. Adil Haider, a trauma surgeon at Johns Hopkins, spoke on helicopter-mediated saves of trauma patients. Totally cool stuff; I’d rate his talk “exotic” – this was as far removed from the kind of work I did on molecular receptors in cancer cells as I’ve ever heard at a medical or journalism meeting of any sort –

Haider indulged the audience, and grabbed my attention, with a bit of history: HEMS, which stands for helicopter-EMS, goes back to the Korean War, like in M*A*S*H. The real-life surgeon-speaker at the JAMA news briefing played a music-replete video showing a person hit by a car and rescued by helicopter. While he and other trauma surgeons see value in HEMS, it’s costly and not necessarily better than GEMS (Ground-EMS). Helicopters tend to draw top nurses, and they deliver patients to Level I or II trauma centers, he said, all of which may favor survival and other, better outcomes after serious injury. Accidents happen; previous studies have questioned the helicopters’ benefit.

The problem is, there’s been no solid randomized trial of HEMS vs. GEMS, nor could there be. (Who’d want to get the slow pick-up with a lesser crew to a local trauma center?) So these investigators did a retrospective cohort study to see what happens when trauma victims 15 years and older are delivered by HEMS or GEMS. They used data from the National Trauma Data Bank (NTDB), which includes nearly 62,000 patients transported by helicopter and over 161,000 patients transported by ground between 2007 and 2009. They selected patients with ISS (Injury severity scores) above 15. They used a “clustering” method to control for differences among trauma centers, and otherwise adjusted for degrees of injury and other confounding variables.

“It’s interesting,” Haider said. “If you look at the unadjusted mortality, the HEMS patients do worse.” But when you control for ISS, you get a 16% increase in odds of survival if you’re taken by helicopter to a Level I trauma center. He referred to Table 3 in the paper. This, indeed, shows a big difference between the “raw” and adjusted data.

When you first look, across the board, you’ll see that actually more patients transported by helicopter, in terms of just the raw percentages, actually die.” – Dr. Samuel Galvagno (DO, PhD), the study’s first author.

The video immediately cuts to the senior author, Haider, who continues:

But when you do an analysis controlling for how severely these patients were injured, the chance of survival improves by about 30 percent, for those patients who are brought by helicopter…

—

Big picture:

What’s clear is that how investigators adjust or manipulate or clarify or frame or present data – you choose the verb – yields differing results. This capability doesn’t just pertain to data on trauma and helicopters. In many Big Data situations, researchers can cut information to impress whatever point they choose.

The report offers a case study of how researchers can use elaborate statistical methods to support a clinical decision in a way that few doctors who read the results are in a position to grasp, to know if the conclusions are valid, or not.

A concluding note –

I appreciated the time allotted for Q&A after the first 3 research presentations. There’s been recent, legitimate questioning of the value of medical conferences. This week’s session, sponsored by JAMA, reinforced to me the value of meeting study authors in person, and having the opportunity to question them about their findings. This is crucial, I know this from my prior experience in cancer research, when I didn’t ask enough hard questions of some colleagues, in public. For the future, at places like TEDMED – where I’ve heard there was no attempt to allow for Q&A – the audience’s concerns can reveal problems in theories, published data and, constructively, help researchers fill in those gaps, ultimately to bring better-quality information, from any sort of study, to light.